Krüppel-like factor(KLF) family proteins are transcription factors that regulate numerous cellular functions, such as cell proliferation, differentiation, and cell death. Posttranslational modification of KLF pro...Krüppel-like factor(KLF) family proteins are transcription factors that regulate numerous cellular functions, such as cell proliferation, differentiation, and cell death. Posttranslational modification of KLF proteins is important for their transcriptional activities and biological functions. One KLF family member with important roles in cell proliferation and tumorigenesis is KLF5. The function of KLF5 is tightly controlled by post-translational modifications, including SUMOylation, phosphorylation, and ubiquitination. Recent studies from our lab and others' have demonstrated that the tumor suppressor FBW7 is an essential E3 ubiquitin ligase that targets KLF5 for ubiquitination and degradation. KLF5 contains functional Cdc4 phospho-degrons(CPDs), which are required for its interaction with FBW7. Mutation of CPDs in KLF5 blocks the ubiquitination and degradation of KLF5 by FBW7. The protein kinase Glycogen synthase kinase 3β is involved in the phosphorylation of KLF5 CPDs. In both cancer cell lines and mousemodels, it has been shown that FBW7 regulates the expression of KLF5 target genes through the modulation of KLF5 stability. In this review, we summarize the current progress on delineating FBW7-mediated KLF5 ubiquitination and degradation.展开更多
Fluorochemicals(FCs)are oxidatively recalcitrant,environmentally persistent,and resistant to most conventional treatment technologies.FCs have unique physiochemical properties derived from fluorine which is the most e...Fluorochemicals(FCs)are oxidatively recalcitrant,environmentally persistent,and resistant to most conventional treatment technologies.FCs have unique physiochemical properties derived from fluorine which is the most electronegative element.Perfluorooctanesulfonate(PFOS),and perfluorooctanoate(PFOA)have been detected globally in the hydrosphere,atmosphere and biosphere.Reducing treatment technologies such as reverses osmosis,nano-filtration and activated carbon can remove FCs from water.However,incineration of the concentrated waste is required for complete FC destruction.Recently,a number of alternative technologies for FC decomposition have been reported.The FC degradation technologies span a wide range of chemical processes including direct photolysis,photocatalytic oxidation,photochemical oxidation,photochemical reduction,thermally-induced reduction,and sonochemical pyrolysis.This paper reviews these FC degradation technologies in terms of kinetics,mechanism,energetic cost,and applicability.The optimal PFOS/PFOA treatment method is strongly dependent upon the FC concentration,background organic and metal concentration,and available degradation time.展开更多
基金Supported by Grants from National Basic Research Program of China,973 program,No.2010CB529704 and No.2012CB910404National Natural Science Foundation of China,No.30800587,No.30971521,and No.31171338+1 种基金the Science and Technology Commission of Shanghai Municipality,No.11DZ2260300a scholar of the Shanghai Rising-Star Program from Science and Technology Commission of Shanghai Municipality,No.09QA1401900 to Wang P
文摘Krüppel-like factor(KLF) family proteins are transcription factors that regulate numerous cellular functions, such as cell proliferation, differentiation, and cell death. Posttranslational modification of KLF proteins is important for their transcriptional activities and biological functions. One KLF family member with important roles in cell proliferation and tumorigenesis is KLF5. The function of KLF5 is tightly controlled by post-translational modifications, including SUMOylation, phosphorylation, and ubiquitination. Recent studies from our lab and others' have demonstrated that the tumor suppressor FBW7 is an essential E3 ubiquitin ligase that targets KLF5 for ubiquitination and degradation. KLF5 contains functional Cdc4 phospho-degrons(CPDs), which are required for its interaction with FBW7. Mutation of CPDs in KLF5 blocks the ubiquitination and degradation of KLF5 by FBW7. The protein kinase Glycogen synthase kinase 3β is involved in the phosphorylation of KLF5 CPDs. In both cancer cell lines and mousemodels, it has been shown that FBW7 regulates the expression of KLF5 target genes through the modulation of KLF5 stability. In this review, we summarize the current progress on delineating FBW7-mediated KLF5 ubiquitination and degradation.
文摘Fluorochemicals(FCs)are oxidatively recalcitrant,environmentally persistent,and resistant to most conventional treatment technologies.FCs have unique physiochemical properties derived from fluorine which is the most electronegative element.Perfluorooctanesulfonate(PFOS),and perfluorooctanoate(PFOA)have been detected globally in the hydrosphere,atmosphere and biosphere.Reducing treatment technologies such as reverses osmosis,nano-filtration and activated carbon can remove FCs from water.However,incineration of the concentrated waste is required for complete FC destruction.Recently,a number of alternative technologies for FC decomposition have been reported.The FC degradation technologies span a wide range of chemical processes including direct photolysis,photocatalytic oxidation,photochemical oxidation,photochemical reduction,thermally-induced reduction,and sonochemical pyrolysis.This paper reviews these FC degradation technologies in terms of kinetics,mechanism,energetic cost,and applicability.The optimal PFOS/PFOA treatment method is strongly dependent upon the FC concentration,background organic and metal concentration,and available degradation time.